Concept:Anaerobic respiration is the incomplete breakdown of glucose without oxygen.Explanation:Aerobic respiration fully oxidises glucose and releases a large amount of energy.Anaerobic respiration only partially breaks down glucose.Energy-rich products like ethanol or lactic acid are formed.As a result, the energy released is much lower.Hence, anaerobic respiration yields less energy than aerobic respiration.Answer:D. less energy than aerobic respiration